Abstract

Although it has been suggested that about 2.5% of the population as a whole shouldbe regarded as having a mild-to-moderate learning disability, only about 0.25% ofthe population is registered as having a learning disability. This paper considerswhy this disparity exists. It is suggested that although 2.5% of the population may bea good estimate for people with IQs less than 70, a better estimate of the proportionof the population who reach a dual criteria of having both a low IQ and social/skilldefects is about 1%. It is pointed out that even if true prevalence rate of learningdisability is nearer to 1% rather than 2.5%, services still only know of a smallproportion of people who could be considered to have a learning disability, andthere are probably a large number of people with unidentified learning disabilities. Itis also noted that the term ‘learning disability’ can be very confusing as it is not clearif it refers to people who have IQs below 70, people with both intellectual andadaptive disabilities or people who have been given a learning disability label. Theimplications of this for services and research are discussed.